Light emitting devices refer to semiconductor devices that emit light generated by recombination of electrons and holes, and are used in variety of fields such as displays, vehicle lamps, general lighting devices, and the like. Particularly, since light emitting devices including nitride semiconductors such as (Al,Ga, In)N have long lifespan, low power consumption, and rapid response rate, lighting apparatuses including such light emitting devices are expected to replace exiting light sources in the art.